The potential of quantum computers lies in their so-called quantum bits, qubits for short. There are different types of qubit technologies available today, all facing the same difficulty: Their states are very unstable. To ensure that they remain controllable long enough to perform computations, they must be cooled to extremely low (cryogenic) temperatures below -270°C. In order to connect large numbers of qubits to the necessary readout and control electronics, electronic components are required that can operate at extremely low temperatures without disturbing the quantum states.
The Fraunhofer Institute for Applied Solid State Physics IAF is researching innovative components for quantum computers together with eight partners in the EU project “SEQUENCE – Cyrogenic 3D Nanoelectronics”. The aim is to develop cryogenic electronics within three years that will make it possible to significantlyincrease the number of usable qubits in a quantum computer. With the help of electronics that can work directly on the cooled qubits, it should be possible in future to do without long connecting cables and elaborate setups. For the development of the planned electronics, the consortium combines competences from universities, research institutes and industry in the fields of Si-CMOS, III-V and 3D integration technologies. Other areas such as space communications and high-performance computing systems will also benefit from this research.